From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Murphy Subject: [PATCH] of/device: Really only set bus DMA mask when appropriate Date: Tue, 6 Nov 2018 11:54:15 +0000 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: hch-jcswGhMUV9g@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, aaro.koskinen-X3B1VOXEql0@public.gmane.org, jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org, linux-mips-6z/3iImG2C8G8FEW9MqTrA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, john.stultz-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org of_dma_configure() was *supposed* to be following the same logic as acpi_dma_configure() and only setting bus_dma_mask if some range was specified by the firmware. However, it seems that subtlety got lost in the process of fitting it into the differently-shaped control flow, and as a result the force_dma==true case ends up always setting the bus mask to the 32-bit default, which is not what anyone wants. Make sure we only touch it if the DT actually said so. Fixes: 6c2fb2ea7636 ("of/device: Set bus DMA mask as appropriate") Reported-by: Aaro Koskinen Reported-by: Jean-Philippe Brucker Signed-off-by: Robin Murphy --- Sorry about that... I guess I only have test setups that either have dma-ranges or where a 32-bit bus mask goes unnoticed :( The Octeon and SMMU issues sound like they're purely down to this, and it's probably related to at least one of John's Hikey woes. Robin. drivers/of/device.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/of/device.c b/drivers/of/device.c index 0f27fad9fe94..757ae867674f 100644 --- a/drivers/of/device.c +++ b/drivers/of/device.c @@ -149,7 +149,8 @@ int of_dma_configure(struct device *dev, struct device_node *np, bool force_dma) * set by the driver. */ mask = DMA_BIT_MASK(ilog2(dma_addr + size - 1) + 1); - dev->bus_dma_mask = mask; + if (!ret) + dev->bus_dma_mask = mask; dev->coherent_dma_mask &= mask; *dev->dma_mask &= mask; -- 2.19.1.dirty